Changed documentation string of --with-unix-socket-path to avoid confusion.

Added ODBC and SQL-99 style LEFT OUTER JOIN.

The following are new reserved words: LEFT, NATURAL, USING.

The client library now uses the value of the environment variable MYSQL_HOST as the default host if it's defined.

SELECT col_name, SUM(expr) now returns NULL for col_name when there are matching rows.

Fixed problem with comparing binary strings and BLOB values with ASCII characters over 127.

Fixed lock problem: when freeing a read lock on a table with multiple read locks, a thread waiting for a write lock would have been given the lock. This shouldn't affect data integrity, but could possibly make mysqld restart if one thread was reading data that another thread modified.

LIMIT offset,count didn't work in INSERT ... SELECT.

Optimized key block caching. This will be quicker than the old algorithm when using bigger key caches.